Two Clinical Center patients had significant illness due to vancomycin resistant and high level gentamicin resistant enterococci. This study attempts to determine the prevalence of vancomycin resistant and high level gentamicin resistant enterococci in the fecal flora of these patients as well as to identify potential risk factors, if any, for acquisition of resistant organisms. Using selective media stool specimens are cultured when patients are admitted to 13E (the cancer ward) and then once a week thereafter. Speciation and antibiotic sensitivities are performed on organisms identified as enterococci. Chart review and statistical analysis will be performed to determine risk factors (such as type of chemotherapy, antibiotics, etc.) for acquisition of these resistant organisms. It is anticipated that further studies (such as plasmic analysis will be undertaken to determine the mechanism of resistance. In addition, other wards in the Clinical Center may be surveyed as deemed necessary. To date two vancomycin moderately resistant, and four gentamicin highly resistant organisms have been isolated. No specific risk factors have been determined.